This is a proposal for a midcareer investigator award in patient-oriented research for Dr. Gregory Lucas, Associate Professor at the Johns Hopkins School of Medicine. Dr. Lucas is medically trained as an infectious diseases specialist and he completed a PhD in clinical investigation at the Bloomberg School of Public Health in 2004. His research career focuses on interventions to improve access to care and outcomes among injection drug users (IDUs), and on chronic kidney disease, a common HIV-related comorbidity that is especially prevalent among IDUs. Injection drug use remains an important mode of HIV transmission worldwide, is a consistent barrier to optimal HIV treatment outcomes, and is a risk factor for medical comorbidity and early mortality. The objective of this proposal is to support a program for mentoring junior investigators and for fostering innovative research. This grant discusses two active research platforms that will serve as a framework for engaging trainees in HIV-related patient-focused research. First, Dr. Lucas is PI of kidney disease cohort designed to assess the roles of HIV, hepatitis C, and active drug use on kidney and cardiovascular disease in a cohort of HIV-infected and HIV-negative subjects. This study includes longitudinal measurements of iohexol clearance (a gold-standard measure of glomerular filtration rate), surrogate measures of cardiovascular disease, and the opportunity to assess putative mechanisms and novel biomarkers through stored specimens. Second, Dr. Lucas is co-PI of a cluster-randomized trial to evaluate the effectiveness of IDU-friendly integrated care centers (ICCs) in India. After baseline data collection and stratification, 12 IDU-prevalent sites in India will be randomized to ICC or control. In the 6 ICC sites, IDU- oriented non-governmental organizations will be scaled-up to provide free HIV testing and on-site ART, in addition to counseling and risk reduction services. After 2 years of service delivery, community-level outcomes will be evaluated with respondent-driven sampling surveys of 1,000 IDUs in each experimental and control site. In addition to these research platforms, Dr. Lucas proposes plans to assist the entry of junior investigators into HIV clinical research through a major commitment to the Johns Hopkins Center for AIDS Research (CFAR) and through his role as kidney disease working group director in the North American AIDS Cohort Collaboration on Research and Design (NA ACCORD). The outstanding environment for HIV research at Johns Hopkins is a key backdrop to this proposal. Dr. Lucas's training, experience, and career goals are well- suited to the objectives of the K24 award.